Silver Arrow was launched by Defense Minister Raimonds Bergmanis at the Adazi military base and sees more than 3,000 troops taking part from Latvia, Lithuania, Estonia, Albania, the United States, Canada, Great Britain, the Netherlands, Romania and Germany.
The 500-strong contingent form the UK announced its arrival via Twitter.
"The training objective is to strengthen the National Armed Forces' cooperation with allies and partners, as well as to train units' capacity to plan and implement protection operations with combat service support element integration," a statement from the Defense Ministry said.
The exercises will involve reserve personnel as well as regular troops ad will also be a chance for Latvia's Joint Command Headquarters to test its effectiveness.
This year's Silver Arrow is notably larger than the equivalent exercises in 2014 and 2015 equivalent, which involved around 2,100 troops.
The Defense Ministry and National Armed Forces are reminding residents and drivers not to be concerned if they see military equipment and personnel on the move and to show consideration for columns of military vehicles on the roads.